1. Field of the Invention
The present invention relates to a portable and hand-held device. More particularly, the present invention relates to a portable and hand-held device for detecting ultrasonic sounds, and making humanly audible sounds responsive thereto.
2. Description of the Prior Art
Numerous innovations for communication systems have been provided in the prior art that will be described. Even though these innovations may be suitable for the specific individual purposes to which they address, however, they differ from the present invention.
A FIRST EXAMPLE, U.S. Pat. No. 4,039,999 to Weston teaches amplitude modulation systems for underwater communication having a number of disadvantages. For example, with a number of divers attempting to communicate simultaneously, intolerable cross-talk occurs. Variable tuning is necessary to overcome this problem. However, the invention disclosed herein uses angle modulation (phase or frequency modulation) which inherently has fewer noise problems and, because of the xe2x80x9ccapture effectxe2x80x9d reduces any cross-talk problems. In an exemplary embodiment an audio transducer feeds a modulator to produce frequency modulated radio frequency signals which are fed to a balanced modulator together with a fixed frequency radio frequency signal from a local oscillator. The output of the balanced modulator comprises ultrasonic frequency signals which are frequency modulated in accordance with the audio signals. Also disclosed is a receiver for such ultrasonic frequency signals. By the use of integrated circuits, a combined ultrasonic transmitter and receiver may be provided in a compact unit adapted to be strapped on the head of a diver.
A SECOND EXAMPLE, U.S. Pat. No. 4,821,326 to MacLeod teaches a non-audible speech generation apparatus and method for producing non-audible speech signals which includes an ultrasonic transducer or vibrator for projecting a series of glottal shaped ultrasonic pulses to the vocal track of a speaker. The glottal pulses, in the approximate frequency spectrum extending from fifteen kilohertz to one hundred five kilohertz, contain harmonics of approximately 30 times the frequency of the acoustical harmonics generated by the vocal cords, but which may nevertheless be amplitude modulated to produce non-audible speech by the speaker""s silently mouthing of words. The ultrasonic speech is then received by an ultrasonic detector disposed outside of the speaker""s mouth and electrically communicated to a translation device which down converts the ultrasonic signals to corresponding signals in the audible frequency range and synthesizes the signals into artificial speech.
A THIRD EXAMPLE, U.S. Pat. No. 5,529,705 to Ackerman et al. teaches a wireless communication system that is undetectable by radio frequency methods for converting audio signals, including human voice, to electronic signals in the ultrasonic frequency range, transmitting the ultrasonic signal by way of acoustical pressure waves across a carrier medium, including gases, liquids, or solids, and reconverting the ultrasonic acoustical pressure waves back to the original audio signal. The ultrasonic speech translator and communication system includes an ultrasonic transmitting device and an ultrasonic receiving device. The ultrasonic transmitting device accepts as input an audio signal such as human voice input from a microphone or tape deck. The ultrasonic transmitting device frequency modulates an ultrasonic carrier signal with the audio signal producing a frequency modulated ultrasonic carrier signal, which is transmitted via acoustical pressure waves across a carrier medium such as gases, liquids or solids. The ultrasonic receiving device converts the frequency modulated ultrasonic acoustical pressure waves to a frequency modulated electronic signal, demodulates the audio signal from the ultrasonic carrier signal, and conditions the demodulated audio signal to reproduce the original audio signal at its output.
A FOURTH EXAMPLE, U.S. Pat. No. 5,661,699 to Sutton teaches an acoustic communication system that comprises: a voice processing circuit which generates a first signal representing a voice message; a noise sensor channel which generates a second signal in response to detecting background noise in an environment; a microcomputer which receives the first and second signals, and provides a third signal to a selected one of first and second output ports of the microcomputer, where the amplitude of the third signal is functionally related to the value of the second signal; an ultrasonic output channel coupled to the first output port and which generates an ultrasonic output signal representing the voice message in response to receiving the third signal; a public address channel coupled to the second output port which generates an audible signal representing the voice message in response to receiving the third signal; and an ultrasonic receiving system which generates an audible output representing the voice message in response to receiving the ultrasonic output signal.
It is apparent that numerous innovations for communication systems have been provided in the prior art that are adapted to be used. Furthermore, even though these innovations may be suitable for the specific individual purposes to which they address, however, they would not be suitable for the purposes of the present invention as heretofore described.
ACCORDINGLY, AN OBJECT of the present invention is to provide a portable and hand-held device for detecting, and making humanly audible, ultrasonic sounds that avoids the disadvantages of the prior art.
ANOTHER OBJECT of the present invention is to provide a portable and hand-held device for detecting, and making humanly audible, ultrasonic sounds that is simple and inexpensive to manufacture.
STILL ANOTHER OBJECT of the present invention is to provide a portable and hand-held device for detecting, and making humanly audible, ultrasonic sounds that is simple to use.
BRIEFLY STATED, STILL YET ANOTHER OBJECT of the present invention is to provide a portable and hand-held device for detecting, and making humanly audible, ultrasonic sounds. The device includes a hand-held housing and circuitry that is contained in the housing. The circuitry includes a microphone that receives the ultrasonic sound, a first low voltage audio power amplifier that strengthens the signal from the microphone, a second low voltage audio power amplifier that further strengthens the signal from the first low voltage audio power amplifier, a 7-stage ripple carry binary counter that lowers the frequency of the signal from the second low voltage audio power amplifier so as to be humanly audible, a third low voltage audio power amplifier that strengthens the signal from the 7-stage ripple carry binary counter, and a speaker that generates a humanly audible sound from the third low voltage audio power amplifier.
The novel features which are considered characteristic of the present invention are set forth in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of the specific embodiments when read and understood in connection with the accompanying drawing.